The present invention relates to techniques for managing programming and memory space of an internal combustion engine control system, and more particularly, but not exclusively, relates to management of a data loading routine residing in memory of an embedded internal combustion engine control system.
To improve performance of internal combustion engines, sophisticated control systems have been developed. These systems typically include a programmable control module that electronically regulates engine operation by adjusting various engine controls in response to information from engine sensors. Operations commonly controlled in this manner include fueling and ignition timing of the engine.
Engine control systems typically include a nonvolatile memory that must reliably retain one or more executable routines for long nonoperational periods over a wide range of temperature and humidity conditions. These high performance nonvolatile memory devices often become a significant source of expense for internal combustion engine control systems. Moreover, the difficulty and expense of adding nonvolatile memory devices in response to increasing processing needs for such systems is often prohibitive. Thus, there is a need for a technique to conserve memory for internal combustion engine control systems. Preferably, this conservation technique is implemented by software and does not impose significant hardware redesign.
Besides control system memory conservation, there are other unmet needs concerning this technology. For example, it is occasionally desired to change information loaded in the nonvolatile memory of the control system. This change may be needed to update various data constants, correct a control system programming glitch, or provide additional control system functions. For systems that store this information in Read Only Memory (ROM), such changes generally require physical replacement of the ROM devices. Even for systems that may have some type of reprogrammable nonvolatile memory, there remains the particularly challenging problem of how to replace a control system routine which itself performs loading of the nonvolatile memory.
The present invention meets these needs and provides other significant benefits and advantages.